Lattice radiation combined with immunotherapy for advanced solid tumors

A Phase II Prospective, Open-Label, Single-Arm Study Evaluating the Efficacy and Safety of Spatially Fractionated Radiotherapy Combined With Immunotherapy in Patients With Advanced Solid Tumors

This trial will test whether combining lattice (spatially fractionated) radiation with immunotherapy helps people with advanced or metastatic solid tumors.

Quick facts

• Phase: Phase 2
• Study type: Interventional
• Enrollment: 30 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Tianjin Medical University Cancer Institute and Hospital (Academic / other)
• Drugs / interventions: immunotherapy, radiation
• Locations: 3 sites (Beijing, Beijing Municipality and 2 other locations)
• Trial ID: NCT07058948 on ClinicalTrials.gov

What this trial studies

This Phase II trial gives lattice radiation therapy (LRT) to the largest tumor by placing 0.5–3 cm high-dose spheres within the gross tumor volume while delivering low-dose radiation to other metastases, followed by immunotherapy given during or within one week after radiotherapy. LRT targets are spaced 2.0–5.0 cm apart, sized to 1–10% of the GTV, and planned to avoid blood vessels and minimize dose to organs at risk, with single-lesion D95 goals of ≥1 Gy/fraction for the GTV and 8–12 Gy/fraction for LRT targets. Other irradiated metastases receive 100–300 cGy × 5 fractions, and brain or bone metastases may receive palliative radiotherapy per routine care. The trial will track treatment-related toxicities, immune-related adverse events, radiographic responses, and exploratory biomarker changes.

Who should consider this trial

Good fit: Adults (≥18) with histologically confirmed advanced or metastatic solid tumors, at least one measurable lesion, KPS ≥70, life expectancy >3 months, adequate organ function, no recent radiotherapy to the proposed site (or prior radiotherapy ≥6 months ago), and no available or tolerable standard therapy.

Not a fit: Patients with poor performance status, significant organ dysfunction, very limited life expectancy, or who cannot receive the specified radiotherapy or immunotherapy are unlikely to benefit from this protocol.

Why it matters

Potential benefit: If successful, this approach could improve local tumor control and stimulate systemic anti-tumor immune responses, potentially shrinking tumors and delaying progression.

How similar studies have performed: Preclinical work and early-phase clinical reports suggest spatially fractionated radiation can boost immune responses, but combined LRT plus checkpoint inhibitor data remain limited and preliminary.

Eligibility criteria

\*\*Inclusion Criteria:\*\*

1. Signed informed consent.
2. Histologically or cytologically confirmed malignant solid tumor.
3. Advanced solid tumor unsuitable for surgery as determined by a multidisciplinary tumor board or consulting physicians.
4. No available standard therapy or inability to tolerate it, with imaging and clinical assessment showing stable disease (SD) or progressive disease (PD).
5. Age ≥18 years on the day of signing informed consent.
6. No prior radiotherapy to the proposed site, or last radiotherapy ≥6 months ago.
7. KPS score ≥70.
8. At least one measurable lesion per RECIST 1.1. Previously irradiated lesions qualify only if significant progression post - radiotherapy.
9. Life expectancy \>3 months.
10. Adequate organ and bone marrow function:

    * Marrow: ANC ≥1.5×10⁹/L, platelets ≥80×10⁹/L, hemoglobin ≥9 g/dL;
    * Liver: Total bilirubin ≤1.5× upper limit of normal (ULN), ALT/AST ≤1.5× ULN;
    * Kidney: Serum creatinine ≤1.5× ULN or creatinine clearance ≥50 ml/min, blood urea nitrogen ≤200 mg/L;
    * Coagulation: INR ≤1.5× ULN, PTT ≤1.5× ULN.
11. Recovery from prior therapy - related adverse events (≤Grade 1 or baseline).
12. Willingness to use appropriate contraception.
13. No radiotherapy contraindications as judged by the radiation oncologist.
14. Agreement to receive both immunotherapy and radiotherapy.

\*\*Exclusion Criteria:\*\*

1. Active central nervous system (CNS) metastases, carcinomatous meningitis, or spinal cord compression.
2. Severe comorbidities such as myocardial infarction within 6 months, severe arrhythmias, or psychosis that may affect treatment completion or result in a life expectancy of \<3 months.
3. Evidence of interstitial lung disease or active/non - infectious pneumonia (e.g., drug - induced, radiation - induced) requiring steroid treatment.
4. History of pulmonary fibrosis, pulmonary artery hypertension, or severe irreversible airway obstruction.
5. Presence of peripheral neuropathy.
6. Severe organ dysfunction (e.g., hepatic, cardiopulmonary failure) that is likely to make radiotherapy intolerable.
7. Known allergy to study drugs or excipients, or a history of severe allergic reaction to any PD - 1 monoclonal antibody.
8. Serious infection within 4 weeks prior to the start of study treatment, including but not limited to hospitalization for infection, bacteremia, or severe pneumonia; or receipt of oral or intravenous antibiotics within 2 weeks prior to study treatment. Patients receiving prophylactic antibiotics (e.g., for urinary tract infections or chronic obstructive pulmonary disease exacerbations) are eligible.
9. Known or suspected active autoimmune disease (e.g., uveitis, colitis, hepatitis, hypophysitis, vasculitis, nephritis, thyroiditis). Exceptions: patients with vitiligo, cured childhood asthma; patients with well - controlled type 1 diabetes on insulin.
10. History of allogeneic organ transplant (except corneal) or allogeneic hematopoietic stem cell transplant.
11. Pregnant or breastfeeding women.
12. Any other condition that the investigator deems a valid reason for disqualification based on the protocol.

Where this trial is running

Beijing, Beijing Municipality and 2 other locations

• Beijing Friendship Hospital, Capital Medical University — Beijing, Beijing Municipality, China (Recruiting)
• Hebei Province Cangzhou Hospital of Integrated Traditional and Western Medicine — Cangzhou, Hebei, China (Recruiting)
• Tianjin Medical University Cancer Institute & Hospital — Tianjin, Tianjin Municipality, China (Recruiting)

Study contacts

• Study coordinator: Ningbo Liu, Doctor

Conditions Solid Cancers; Radiotherapy; Immune Checkpoint Inhibitor; Lung Cancer; spatially fractionated radiotherapy; solid cancers; immune checkpoint inhibitor